From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8785A2FFDF8; Tue, 12 May 2026 16:14:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778602445; cv=none; b=OwK8OkL+EwbIb+yDNegEksTbcLpwZ/PmB0NLG/LtrSyMu1F5F5wasq+yYUZwZhpxzMRiNv1T39d1wevVmjTGXpt5W5sJpJ/DSpo3A5q1IFBOAT1U1vzxxE4AbsE7wymFP2R8EtgRuwgcBW3VxYYAz1HBujUdiU/2P2EHSz3hc6c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778602445; c=relaxed/simple; bh=GHZWor7rdy45tprIWlWstOcDkMP3M+aEv6hEteW8EN4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=pMAzgSuRHcJ1pgvwK0ve9GCTMmTpEfkw0AmB8kr1bYk+RArExJxlCRwAtOD4gSCQg4xC107+OvY+WSaIe7Go7J+XXeOGn5CP48iwCR+Zuj3eRBL2y8TXtJh4FMMoHDjnphCMbBbrdE144pUBgP+SBTbVFIyBVquNMWSU7MzOcoA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=TY7M8Nt4; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="TY7M8Nt4" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 55E471650; Tue, 12 May 2026 09:13:57 -0700 (PDT) Received: from [192.168.178.24] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E60113F836; Tue, 12 May 2026 09:13:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778602442; bh=GHZWor7rdy45tprIWlWstOcDkMP3M+aEv6hEteW8EN4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=TY7M8Nt4UDSmdhmrU1PKycF2lKfojYvEgKZZTllA6T6EIcJJAOG5s0dTV1+BBqFmc DwrW/PEUVkuEBxsmvpIePwV8KDGXTgriDtnkCq1esQvuHgd2gSCob83CbpWw6kv0ex vKB4hBVG18OeOxX6YGT7kP5rPYTjgAVZSs+/abZA= Message-ID: <15389814-e6d3-43bf-967b-38d0fc8f8c52@arm.com> Date: Tue, 12 May 2026 18:13:58 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/5] arm_mpam: Parse the rest of the ACPI table To: Ben Horgan , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260429141339.3171205-1-andre.przywara@arm.com> <20260429141339.3171205-2-andre.przywara@arm.com> Content-Language: en-US From: Andre Przywara In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Ben, On 5/8/26 12:21, Ben Horgan wrote: > Hi Andre, > > On 4/29/26 15:13, Andre Przywara wrote: >> From: James Morse >> >> The MPAM ACPI table lists the MPAM MSCs and indicates which resources >> in the system they control. Not everything this table can describe is >> supported by resctrl, e.g. memory-side-caches. >> >> Add the additional table parsing to avoid reporting these as 'unknown' >> to the MPAM driver. This allows class+component hierarchys to be built. >> >> Until resctrl has support for any of these resources, users would be >> in-kernel managers of a resource/PARTID or perf to query bandwidth >> counters on a resource resctrl is unaware of. > > Does this patch give us anything needed for MPAM-Fb? It seems to just add > parsing for things we don't support in the MPAM driver. I think you are right, this just parses more resource types from the MSC table, but is otherwise unrelated to MPAM-Fb. I probably just cargo-culted this patch all the time ;-) Will drop it now. Cheers, Andre. > > Thanks, > > Ben > >> >> Signed-off-by: James Morse >> Signed-off-by: Andre Przywara >> --- >> drivers/acpi/arm64/mpam.c | 91 +++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 88 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/acpi/arm64/mpam.c b/drivers/acpi/arm64/mpam.c >> index 84963a20c3e7..99c2bdbb3314 100644 >> --- a/drivers/acpi/arm64/mpam.c >> +++ b/drivers/acpi/arm64/mpam.c >> @@ -95,17 +95,51 @@ static void acpi_mpam_parse_irqs(struct platform_device *pdev, >> res[(*res_idx)++] = DEFINE_RES_IRQ_NAMED(irq, "error"); >> } >> >> -static int acpi_mpam_parse_resource(struct mpam_msc *msc, >> +#define UUID_MPAM_INTERCONNECT_TABLE "fe2bd645-033b-49e6-9479-2e0b8b21d1cd" >> + >> +struct acpi_mpam_interconnect_descriptor_table { >> + u8 type_uuid[16]; >> + u32 num_descriptors; >> +}; >> + >> +struct acpi_mpam_interconnect_descriptor { >> + u32 source_id; >> + u32 destination_id; >> + u8 link_type; >> + u8 reserved[3]; >> +}; >> + >> +static int acpi_mpam_parse_resource(struct acpi_mpam_msc_node *tbl_msc, >> + struct mpam_msc *msc, >> struct acpi_mpam_resource_node *res) >> { >> + struct acpi_mpam_interconnect_descriptor_table *tbl_int_tbl; >> + struct acpi_mpam_interconnect_descriptor *tbl_int; >> + guid_t int_tbl_uuid, spec_uuid; >> int level, nid; >> u32 cache_id; >> + off_t offset; >> >> + /* >> + * Class IDs are somewhat arbitrary, but need to be co-ordinated. >> + * 0-N are caches, >> + * 64, 65: Interconnect, but ideally these would appear between the >> + * classes the controls are adjacent to. >> + * 128: SMMU, >> + * 192-192+level: Memory Side Caches, nothing checks that N is a >> + * small number. >> + * 255: Memory Controllers >> + * >> + * ACPI devices would need a class id allocated based on the _HID. >> + * >> + * Classes that the mpam driver can't currently plumb into resctrl >> + * are registered as UNKNOWN. >> + */ >> switch (res->locator_type) { >> case ACPI_MPAM_LOCATION_TYPE_PROCESSOR_CACHE: >> cache_id = res->locator.cache_locator.cache_reference; >> level = find_acpi_cache_level_from_id(cache_id); >> - if (level <= 0) { >> + if (level <= 0 || level >= 64) { >> pr_err_once("Bad level (%d) for cache with id %u\n", level, cache_id); >> return -EINVAL; >> } >> @@ -120,6 +154,57 @@ static int acpi_mpam_parse_resource(struct mpam_msc *msc, >> } >> return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_MEMORY, >> MPAM_CLASS_ID_DEFAULT, nid); >> + case ACPI_MPAM_LOCATION_TYPE_SMMU: >> + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_UNKNOWN, >> + 128, res->locator.smmu_locator.smmu_interface); >> + case ACPI_MPAM_LOCATION_TYPE_MEMORY_CACHE: >> + cache_id = res->locator.mem_cache_locator.reference; >> + level = res->locator.mem_cache_locator.level; >> + if (192 + level >= 255) { >> + pr_err_once("Bad level for memory side cache with reference %u\n", >> + cache_id); >> + return -EINVAL; >> + } >> + >> + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_CACHE, >> + 192 + level, cache_id); >> + >> + case ACPI_MPAM_LOCATION_TYPE_INTERCONNECT: >> + /* Find the descriptor table, and check it lands in the parent msc */ >> + offset = res->locator.interconnect_ifc_locator.inter_connect_desc_tbl_off; >> + if (offset >= tbl_msc->length) { >> + pr_err_once("Bad offset for interconnect descriptor on msc %u\n", >> + tbl_msc->identifier); >> + return -EINVAL; >> + } >> + tbl_int_tbl = ACPI_ADD_PTR(struct acpi_mpam_interconnect_descriptor_table, >> + tbl_msc, offset); >> + guid_parse(UUID_MPAM_INTERCONNECT_TABLE, &spec_uuid); >> + import_guid(&int_tbl_uuid, tbl_int_tbl->type_uuid); >> + if (guid_equal(&spec_uuid, &int_tbl_uuid)) { >> + pr_err_once("Bad UUID for interconnect descriptor on msc %u\n", >> + tbl_msc->identifier); >> + return -EINVAL; >> + } >> + >> + offset += sizeof(*tbl_int_tbl); >> + offset += tbl_int_tbl->num_descriptors * sizeof(*tbl_int); >> + if (offset >= tbl_msc->length) { >> + pr_err_once("Bad num_descriptors for interconnect descriptor on msc %u\n", >> + tbl_msc->identifier); >> + return -EINVAL; >> + } >> + >> + tbl_int = ACPI_ADD_PTR(struct acpi_mpam_interconnect_descriptor, >> + tbl_int_tbl, sizeof(*tbl_int_tbl)); >> + cache_id = tbl_int->source_id; >> + >> + /* Unknown link type? */ >> + if (tbl_int->link_type != 0 && tbl_int->link_type == 1) >> + return 0; >> + >> + return mpam_ris_create(msc, res->ris_index, MPAM_CLASS_UNKNOWN, >> + 64 + tbl_int->link_type, cache_id); >> default: >> /* These get discovered later and are treated as unknown */ >> return 0; >> @@ -150,7 +235,7 @@ int acpi_mpam_parse_resources(struct mpam_msc *msc, >> return -EINVAL; >> } >> >> - err = acpi_mpam_parse_resource(msc, resource); >> + err = acpi_mpam_parse_resource(tbl_msc, msc, resource); >> if (err) >> return err; >> >